Trim any loose skin from the birds, remove any feathers and cut off the parson's nose from each one.
Dissolve the saffron in a little of the juice from the tomatoes and paint the birds all over with that.
Fold the coriander a few times and cut roughly.
Put most of it into the cavities of the birds, and place them in a small roasting-tin with the remaining coriander and tomatoes.
The tin should be just big enough to take them.
Chop the garlic finely and sprinkle or squeeze the juice over the birds.
Dot with the butter and season very lightly with salt and pepper.
Turn the birds on to their sides and cover the dish with foil.
Roast at 180°C/350°F/Gas Mark 4 for about 30 minutes or until the birds are cooked through, turning them on to their other sides half way through the cooking time.
Serve on plain rice or chopped potatoes that have been boiled in their skins.